Impact of high-pressure processing on hemolymph, color, lipid globular structure and oxidation of the edible portion of blood clams

Impact of high-pressure processing (HP-P) on hemolymph and lipid globular structures of the edible portion (EP) of blood clams (BC) was investigated. HP-P above 400 MPa decreased heme iron content, while upsurged non-heme iron content. Increasing pressure induced gaps and abnormal hemocyte cell arrangements. However, HP-P at 300 MPa improved and maintained total hemocyte counts, the heme iron content, and a*-value in BC-EP. For lipid globular structures, the mean diameter drastically decreased when an HP-P pressure of 600 MPa was employed. HP-P at higher pressure induced lipid oxidation, along with decreases in monounsaturated and polyunsaturated fatty acids as well as increases in thiobarbituric acid reactive substances and peroxide value. FTIR spectra displayed a reduction in phosphate groups and cis double bonds in lipids from HP-P treated BC, compared to controls. Therefore, HP-P at 300 MPa is recommended for preparing ready-to-cook BC with less tissue damage and lipid oxidation.

GPX7 reduces chondrocyte inflammation and extracellular matrix degradation triggered by IL‑1β, via a mechanism mediated by ferroptosis

During osteoarthritis (OA), chondrocytes become highly active, with increased matrix synthesis and inflammatory cytokine‑induced catabolic pathways. Early intervention strategies targeting pathological changes may attenuate or halt disease progression. The present study aimed to reveal the role of glutathione peroxidase (GPX)7 in OA. For this purpose, a research model was established by inducing C28/I2 human chondrocytes with interleukin (IL)‑1β, and the expression level of GPX7 was determined. To explore its roles, C28/I2 cells were transfected to gain GPX7 overexpression. The effects of GPX7 overexpression on intracellular inflammation, extracellular matrix (ECM) degradation, apoptosis and ferroptosis were then evaluated. In addition, the cells were treated with the ferroptosis inducer, erastin, and its effects on the aforementioned phenotypes were assessed. The level of GPX7 was decreased in response to IL‑1β treatment, and GPX7 overexpression suppressed cellular inflammation, ECM degradation and apoptosis. Moreover, the reduction of lipid peroxidation, ferrous ions and transferrin indicated that GPX7 overexpression inhibited ferroptosis. Subsequently, inflammation, ECM degradation and apoptosis were found to be promoted in the cells upon treatment with erastin. These findings suggested that the regulatory role of GPX7 may be mediated by a pathway involving ferroptosis. On the whole, the present study revealed that GPX7 reduces IL‑1β‑induced chondrocyte inflammation, apoptosis and ECM degradation partially through a mechanism involving ferroptosis. The results of the present study lay a theoretical foundation for subsequent OA‑related research and may enable the development of translational strategies for the treatment of OA.

Effects of 2,4-dichlorophenol on non-specific immunity, histopathological lesions, and redox balance in African Catfish, clarias gariepinus (Burchell, 1822)

The toxic effects of 2, 4-dichlorophenol (2, 4-DCP) on aquatic organisms are well-established; however, the details regarding the mechanisms underlying the toxicity, especially immunotoxicity are poorly understood. Consequently, the aim of this study was to investigate the histopathologic, oxidative stress and immunotoxic effects attributed to exposure to sublethal concentrations of 2,4-DCP in the African catfish, Clarias gariepinus. Juvenile C. gariepinus were exposed to 0.4, 0.8, or 1.6 mg/L 2, 4-DCP for 28 days after which blood and head kidney were extracted for the determination of various nonspecific innate immune parameters while the liver was excised for histopathology examination and measurement of oxidative stress biomarkers. Control fish were maintained in water spiked 10 µL/L ethanol, representing the solvent control. A significant increase was noted in the activities of lactate dehydrogenase and superoxide dismutase as well as in levels of lipid peroxidation and DNA fragmentation in a dose-dependent manner, with higher adverse effects observed at the highest concentration tested (1.6 mg/L). The total white blood cells (WBC) count was significantly elevated in fish exposed to 2,4-DCP compared to control. Myeloperoxidase content was decreased significantly in fish exposed to 2,4-DCP especially at the highest concentration (1.6 mg/L) compared to controls. The respiratory burst activity did not differ markedly amongst groups. Histopathological lesions noted included edema, leucocyte infiltration, and depletion of hemopoietic tissue in the head kidney of exposed fish. There was significant upregulation in the mRNA expression of tumor necrosis factor (TNF-α) and heat shock protein 70 (HSP 70) but downregulation of major histocompatibility complex 2 (MHC 2) in exposed fish. Data demonstrated that exposure to 2,4-DCP resulted in histopathological lesions, oxidative stress, and compromised immune system in C. gariepinus.

ALOX15B controls macrophage cholesterol homeostasis via lipid peroxidation, ERK1/2 and SREBP2

Macrophage cholesterol homeostasis is crucial for health and disease and has been linked to the lipid-peroxidizing enzyme arachidonate 15-lipoxygenase type B (ALOX15B), albeit molecular mechanisms remain obscure. We performed global transcriptome and immunofluorescence analysis in ALOX15B-silenced primary human macrophages and observed a reduction of nuclear sterol regulatory element-binding protein (SREBP) 2, the master transcription factor of cellular cholesterol biosynthesis. Consequently, SREBP2-target gene expression was reduced as were the sterol biosynthetic intermediates desmosterol and lathosterol as well as 25- and 27-hydroxycholesterol. Mechanistically, suppression of ALOX15B reduced lipid peroxidation in primary human macrophages and thereby attenuated activation of mitogen-activated protein kinase ERK1/2, which lowered SREBP2 abundance and activity. Low nuclear SREBP2 rendered both, ALOX15B-silenced and ERK1/2-inhibited macrophages refractory to SREBP2 activation upon blocking the NPC intracellular cholesterol transporter 1. These studies suggest a regulatory mechanism controlling macrophage cholesterol homeostasis based on ALOX15B-mediated lipid peroxidation and concomitant ERK1/2 activation.

Peroxiredoxin 6 suppresses ferroptosis in lung endothelial cells

Peroxiredoxin 6 (Prdx6) repairs peroxidized membranes by reducing oxidized phospholipids, and by replacing oxidized sn-2 fatty acyl groups through hydrolysis/reacylation by its phospholipase A2 (aiPLA2) and lysophosphatidylcholine acyltransferase activities. Prdx6 is highly expressed in the lung, and intact lungs and cells null for Prdx6 or with single-point mutations that inactivate either Prdx6-peroxidase or aiPLA2 activity alone exhibit decreased viability, increased lipid peroxidation, and incomplete repair when exposed to paraquat, hyperoxia, or organic peroxides. Ferroptosis is form of cell death driven by the accumulation of phospholipid hydroperoxides. We studied the role of Prdx6 as a ferroptosis suppressor in the lung. We first compared the expression Prdx6 and glutathione peroxidase 4 (GPx4) and visualized Prdx6 and GPx4 within the lung. Lung Prdx6 mRNA levels were five times higher than GPx4 levels. Both Prdx6 and GPx4 localized to epithelial and endothelial cells. Prdx6 knockout or knockdown sensitized lung endothelial cells to erastin-induced ferroptosis. Cells with genetic inactivation of either aiPLA2 or Prdx6-peroxidase were more sensitive to ferroptosis than WT cells, but less sensitive than KO cells. We then conducted RNA-seq analyses in Prdx6-depleted cells to further explore how the loss of Prdx6 sensitizes lung endothelial cells to ferroptosis. Prdx6 KD upregulated transcriptional signatures associated with selenoamino acid metabolism and mitochondrial function. Accordingly, Prdx6 deficiency blunted mitochondrial function and increased GPx4 abundance whereas GPx4 KD had the opposite effect on Prdx6. Moreover, we detected Prdx6 and GPx4 interactions in intact cells, suggesting that both enzymes cooperate to suppress lipid peroxidation. Notably, Prdx6-depleted cells remained sensitive to erastin-induced ferroptosis despite the compensatory increase in GPx4. These results show that Prdx6 suppresses ferroptosis in lung endothelial cells and that both aiPLA2 and Prdx6-peroxidase contribute to this effect. These results also show that Prdx6 supports mitochondrial function and modulates several coordinated cytoprotective pathways in the pulmonary endothelium.

Molecular dynamics of structural effects of reactive carbonyl species derivate of lipid peroxidation on bovine serum albumin

BACKGROUND

Serum albumin is the most abundant protein in the Mammalia blood plasma at where plays a decisive role in the transport wide variety of hydrophobic ligands. BSA undergoes oxidative modifications like the carbonylation by the reactive carbonyl species (RCSs) 4-hydroxy-2-nonenal (HNE), 4 hydroxy-2-hexenal (HHE), malondialdehyde (MDA) and 4-oxo-2-nonenal (ONE), among others. The structural and functional changes induced by protein carbonylation have been associated with the advancement of neurodegenerative, cardiovascular, metabolic and cancer diseases.

METHODS

To elucidate structural effects of protein carbonylation with RCSs on BSA, parameters for six new non-standard amino acids were designated and molecular dynamics simulations of its mono‑carbonylated-BSA systems were conducted in the AMBER force field. Trajectories were evaluated by RMSD, RMSF, PCA, RoG and SASA analysis.

RESULTS

An increase in the conformational instability for all proteins modified with local changes were observed, without significant changes on the BSA global three-dimensional folding. A more relaxed compaction level and major solvent accessible surface area for modified systems was found. Four regions of high molecular fluctuation were identified in all modified systems, being the subdomains IA and IIIB those with the most remarkable local conformational changes. Regarding essential modes of domain movements, it was evidenced that the most representatives were those related to IA subdomain, while IIIB subdomain presented discrete changes.

CONCLUSIONS

RCSs induces local structural changes on mono‑carbonylated BSA. Also, this study extends our knowledge on how carbonylation by RCSs induce structural effects on proteins.

Activation of lipophagy is required for RAB7 to regulate ferroptosis in sepsis-induced acute kidney injury

Sepsis-induced acute kidney injury (S-AKI) is the most common type of acute kidney injury (AKI), accompanied by elevated morbidity and mortality rates. This study investigated the mechanism by which lipid droplets (LDs) degraded via autophagy (lipophagy)required for RAB7 regulated ferroptosis in the pathogenesis of S-AKI. Here, we constructed the S-AKI model in vitro and in vivo to elucidate the potential relationship of lipophagy and ferroptosis, and we first confirmed that the activation of lipophagy promoted renal tubular epithelial cell ferroptosis and renal damage in S-AKI. The results showed that lipopolysaccharide (LPS) induced a marked increase in lipid peroxidation and ferroptosis, which were rescued by ferrstain-1 (Fer-1), an inhibitor of ferroptosis. In addition, LPS induced the remarkable activation of RAB7-mediated lipophagy. Importantly, silencing RAB7 alleviated LPS-induced lipid peroxidation and ferroptosis. Thus, the present study demonstrated the potential significant role of ferroptosis and lipophagy in sepsis-induced AKI, and contributed to better understanding of the pathogenesis and treatment targets of AKI.

Imbalance of Plasma Copper and Zinc Levels and the Association Between the Cu/Zn Ratio and Lipid Peroxidation in Algerian Bipolar Patients

Trace elements, through their interaction with biomolecules, can play an important role in the pathophysiology of bipolar disorder and protect against oxidative stress effects. The purpose of this study is to examine plasma concentration levels of zinc (Zn) and copper (Cu) of Algerian patients, diagnosed with bipolar disorder, and to compare these levels with those of healthy controls. The Cu/Zn ratio was calculated to explore a possible correlation between these elements and lipid peroxidation in the study groups. A total of 33 patients diagnosed with bipolar disorder and 38 healthy subjects participated in this study. Plasma copper and zinc concentrations were measured using a polarographic analyzer. The marker of plasma lipid peroxidation (Malondialdehyde: MDA) was determined by UV spectrophotometry. Plasma Cu concentrations were higher in patients compared to controls (p < 0.05), while the Zn level was significantly lower. Consequently, the Cu/Zn ratio was significantly different between patients and controls. Regarding MDA, no significant difference was noticed between the two study groups. However, in patients, a negative correlation was found between MDA and Cu/Zn ratio (r= -0.38, p= 0.027). These results suggested that an elevated Cu/Zn ratio is associated with attenuated lipid peroxidation in our bipolar patients.

Green infant formula analysis: Optimizing headspace solid-phase microextraction of carbonyl compounds associated with lipid peroxidation using GC-MS and pentafluorophenylhydrazine derivatization

The refinement and optimization of a method combining headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) was successfully performed for the first time to determine seven carbonyl and dicarbonyl compounds, including glyoxal, methylglyoxal, dimethylglyoxal, and malondialdehyde in infant formulae, related to lipid peroxidation. HS-SPME was utilized for simultaneous extraction and derivatization with pentafluorophenylhydrazine (PFPH). Critical parameters such as temperature, pH, extractive phase, and salting-out were meticulously investigated and fine-tuned by an asymmetrical 2232//9 screening design to ensure the method's efficacy and reliability. Optimal conditions included a PFPH concentration of 5 g/L, pH 5.0, head-space extraction at 60 °C within 10 min, utilizing a DVB/CAR/PDMS coating, and a 20% w/w salting-out. The analytical validation of this method, compliant with FDA guidelines, demonstrated exceptional linearity, sensitivity, specificity, precision (RSD ≤13.8%), and accuracy (84.8% ≤ recovery ≤111.5%). The metric approach AGREEprep confirms its eco-friendliness, marking a significant step towards an environmentally conscious approach in infant formula analysis. An occurrence study conducted on 25 infant formula samples revealed widespread carbonyl and dicarbonyl compounds in both powdered and liquid variants. ANOVA results exhibited variations in compound concentrations among different sample groups. Clustering analyses delineated distinct groups based on carbonyl content, indicating the potential of these compounds as markers for lipid peroxidation and food quality assessment. This method serves as a valuable tool for evaluating infant formula quality, stability towards oxidation, and safety.

Malondialdehyde levels and bioaccessibility in healthy diet bars: A gastrointestinal digestion model

Malondialdehyde (MDA), which is composed when n-6 and n-3 PUFAs are peroxidized, has been utilized as an indicator of lipid peroxidation and has been considered neurotoxic, cytotoxic, and mutagenic. This study aimed to determine the bioaccessibility level of MDA in diet bars sold as healthy snacks in the market using in vitro gastrointestinal digestive model. In our study, 28 different diet bar samples were bought from markets in Istanbul. MDA contents of the products were determined by the HPLC-FLD method. The investigation showed that diet bars had an average MDA concentration of 116.25 μg/100 g before digestion, while the average MDA concentration was 90.50 μg/100 g after in vitro digestion. In line with these data, the average MDA bioaccessibility of 28 diet bar samples was calculated as 77.3%. For this reason, more studies are needed to understand the relationship between both the MDA content and the reaction and nutritional components.

Exacerbated ischemia-reperfusion injury in fatty livers is mediated by lipid peroxidation stress and ferroptosis

BACKGROUND

Ischemia-reperfusion injury is a common problem in liver surgery and transplantation. Although ischemia-reperfusion injury is known to be more pronounced in fatty livers, the underlying mechanisms for this difference remain poorly understood. We hypothesized that ferroptosis plays a significant role in fatty liver ischemia-reperfusion injury due to increased lipid peroxidation in the presence of stored iron in the fatty liver. To test this hypothesis, the ferroptosis pathway was evaluated in a murine fatty liver ischemia-reperfusion injury model.

METHODS

C57BL6 mice were fed with a normal diet or a high fat, high sucrose diet for 12 weeks. At 22 weeks of age, liver ischemia-reperfusion injury was induced through partial (70%) hepatic pedicle clamping for 60 minutes, followed by 24 hours of reperfusion before tissue harvest. Acyl-coenzyme A synthetase long-chain family member 4 and 4-hydroxynonenal were quantified in the liver tissues. In separate experiments, liproxstatin-1 or vehicle control was administered for 7 consecutive days before liver ischemia-reperfusion injury.

RESULTS

Exacerbated ischemia-reperfusion injury was observed in the livers of high fat, high sucrose diet fed mice. High fat, high sucrose diet + ischemia-reperfusion injury (HDF+IRI) livers had a significantly greater abundance of acyl-coenzyme A synthetase long-chain family member 4 and 4-hydroxynonenal compared with normal diet + ischemia-reperfusion injury (ND+IRI) livers or sham fatty livers, which indicated an increase of ferroptosis. HFD fed animals receiving liproxstatin-1 injections had a significant reduction in serum aspartate transaminase and alanine transaminase after ischemia-reperfusion injury, consistent with attenuation of ischemia-reperfusion injury in the liver.

CONCLUSION

Ferroptosis plays a significant role in ischemia-reperfusion injury in fatty livers. Inhibiting ferroptotic pathways in the liver may serve as a novel therapeutic strategy to protect the fatty liver in the setting of ischemia-reperfusion injury.

Correlations of dynamic changes in lipid and protein of salted large yellow croaker during storage

Protein and lipid are two major components that undergo significant changes during processing of aquatic products. This study focused on the protein oxidation, protein conformational states, lipid oxidation and lipid molecule profiling of salted large yellow croaker during storage, and their correlations were investigated. The degree of oxidation of protein and lipid was time-dependent, leading to an increase in carbonyl content and surface hydrophobicity, a decrease in sulfhydryl groups, and an increase in conjugated diene, peroxide value and thiobarbituric acid reactive substances value. Oxidation caused protein structure denaturation and aggregation during storage. Lipid composition and content changed dynamically, with polyunsaturated phosphatidylcholine (PC) was preferentially oxidized compared to polyunsaturated triacylglycerol. Correlation analysis showed that the degradation of polyunsaturated key differential lipids (PC 18:2_20:5, PC 16:0_22:6, PC 16:0_20:5, etc.) was closely related to the oxidation of protein and lipid. The changes in protein conformation and the peroxidation of polyunsaturated lipids mutually promote each other's oxidation process.

FAdV-4-induced ferroptosis affects fat metabolism in LMH cells

Ferroptosis is a form of controlled cell death that was first described relatively recently and that is dependent on the formation and accumulation of lipid free radicals through an iron-mediated mechanism. A growing body of evidence supports the close relationship between pathogenic infections and ferroptotic cell death, particularly for viral infections. Ferroptosis is also closely tied to the pathogenic development of hepatic steatosis and other forms of liver disease. Fowl adenovirus serotype 4 (FAdV-4) is a hepatotropic aviadenovirus causing hydropericardium syndrome (HPS) that is capable of impacting fat metabolism. However, it remains uncertain as to what role, if any, ferroptotic death plays in the context of FAdV-4 infection. Here, FAdV-4 was found to promote ferroptosis via the p53-SLC7A11-GPX4 axis, while ferrostain-1 was capable of inhibiting this FAdV-4-mediated ferroptotic death through marked reductions in lipid peroxidation. The incidence of FAdV-4-induced fatty liver was also found to be associated with the activation of ferroptotic activity. Together, these results offer novel insights regarding potential approaches to treating HPS.

Cardiomyocyte-specific deletion of the mitochondrial transporter Abcb10 causes cardiac dysfunction via lysosomal-mediated ferroptosis

Heart function is highly dependent on mitochondria, which not only produce energy but also regulate many cellular functions. Therefore, mitochondria are important therapeutic targets in heart failure. Abcb10 is a member of the ABC transporter superfamily located in the inner mitochondrial membrane and plays an important role in haemoglobin synthesis, biliverdin transport, antioxidant stress, and stabilization of the iron transporter mitoferrin-1. However, the mechanisms underlying the impairment of mitochondrial transporters in the heart remain poorly understood. Here, we generated mice with cardiomyocyte-specific loss of Abcb10. The Abcb10 knockouts exhibited progressive worsening of cardiac fibrosis, increased cardiovascular risk markers and mitochondrial structural abnormalities, suggesting that the pathology of heart failure is related to mitochondrial dysfunction. As the mitochondrial dysfunction was observed early but mildly, other factors were considered. We then observed increased Hif1α expression, decreased NAD synthase expression, and reduced NAD+ levels, leading to lysosomal dysfunction. Analysis of ABCB10 knockdown HeLa cells revealed accumulation of Fe2+ and lipid peroxides in lysosomes, leading to ferroptosis. Lipid peroxidation was suppressed by treatment with iron chelators, suggesting that lysosomal iron accumulation is involved in ferroptosis. We also observed that Abcb10 knockout cardiomyocytes exhibited increased ROS production, iron accumulation, and lysosomal hypertrophy. Our findings suggest that Abcb10 is required for the maintenance of cardiac function and reveal a novel pathophysiology of chronic heart failure related to lysosomal function and ferroptosis.

RNA-seq combined network pharmacology reveals that Fu-Gan-Wan (FGW) inhibits liver fibrosis via NF-κB/CCL2/CCR2 and lipid peroxidation via Nrf2/HMOX1 signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Liver fibrosis is a serious complication of liver disease characterized by excessive collagen deposition, without effective therapeutic agents in the clinic. Fu-Gan-Wan (FGW) is an empirical formula used for the clinical treatment of hepatitis and cirrhosis. It has been shown to reverse experimental liver fibrosis. However, its corresponding mechanisms remain unclear.

AIM OF THE REVIEW

This study aimed to elucidate the key pathways and target genes of FGW in attenuating liver fibrosis.

MATERIALS AND METHODS

The therapeutic effects of different doses of FGW on liver fibrosis were investigated using a 2 mL/kg 15% CCl4-induced mouse model. Then, RNA-seq combined with network pharmacology was used to analyze the key biological processes and signaling pathways underlying the anti-liver fibrosis exertion of FGW. These findings were validated in a TGF-β1-induced model of activation and proliferation of mouse hepatic stellate cell line JS-1. Finally, the key signaling pathways and molecular targets were validated using animal tissues, and the effect of FGW on tissue lipid peroxidation was additionally observed.

RESULTS

We found that 19.5 g/kg FGW significantly down-regulated CCl4-induced elevation of hepatic ALT and AST, decreased collagen deposition, and inhibited the expression of pro-fibrotic factors α-SMA, COL1α1, CTGF, TIMP-1, as well as pro-inflammatory factor TGF-β1. Additionally, FGW at doses of 62.5, 125, and 250 μg/mL dose-dependently blocked JS-1 proliferation, migration, and activation. Furthermore, RNA-seq identified the NF-κB signaling pathway as a key target molecular pathway for FGW against liver fibrosis, and network pharmacology combined with RNA-seq focused on 11 key genes. Significant changes were identified in CCL2 and HMOX1 by tissue RT-PCR, Western blot, and immunohistochemistry. We further demonstrated that FGW significantly attenuated CCl4-induced increases in p-p65, CCL2, CCR2, and HMOX1, while significantly elevating Nrf2. Finally, FGW significantly suppressed the accumulation of lipid peroxidation products MDA and 4-HNE and reconfigured the oxidation-reduction balance, including promoting the increase of antioxidants GPx, GSH, and SOD, and the decrease of peroxidation products ROS and GSSG.

CONCLUSIONS

This study demonstrated that FGW exhibits potential in mitigating CCl4-induced hepatic fibrosis, lipid peroxidation, and iron metabolism disorders in mice. This effect may be mediated through the NF-κB/CCL2/CCR2 and Nrf2/HMOX1 pathways.

Understanding the transition to viable but non-culturable state in Escherichia coli W3110: a comprehensive analysis of potential spectrochemical biomarkers

The viable but non-culturable (VBNC) state is considered a survival strategy employed by bacteria to endure stressful conditions, allowing them to stay alive. Bacteria in this state remain unnoticed in live cell counts as they cannot proliferate in standard culture media. VBNC cells pose a significant health risk because they retain their virulence and can revive when conditions normalize. Hence, it is crucial to develop fast, reliable, and cost-effective methods to detect bacteria in the VBNC state, particularly in the context of public health, food safety, and microbial control assessments. This research examined the biomolecular changes in Escherichia coli W3110 induced into the VBNC state in artificial seawater under three different stress conditions (temperature, metal, and antibiotic). Initially, confirmation of VBNC cells under various stresses was done using fluorescence microscopy and plate counts. Subsequently, lipid peroxidation was assessed through the TBARS assay, revealing a notable increase in peroxidation end-products in VBNC cells compared to controls. ATR-FTIR spectroscopy and chemomometrics were employed to analyze biomolecular changes, uncovering significant spectral differences in RNA, protein, and nucleic acid concentrations in VBNC cells compared to controls. Notably, RNA levels increased, while protein and nucleic acid amounts decreased. ROC analyses identified the 995 cm- 1 RNA band as a consistent marker across all studied stress conditions, suggesting its potential as a robust biomarker for detecting cells induced into the VBNC state under various stressors.

High-throughput synchronous erythrocyte cellular antioxidant activity and protection screening of phenolic-rich extracts: Protocol validation and applications

Oxidative/nitrosative damage takes part in chronic disease development, which generates an urgent need for intervention and better therapies to manage them. The scientific community has demanded easy-to-run, cheap, and reliable methods for cellular antioxidant activity assays. This work standardised and validated an erythrocyte cellular antioxidant activity and membrane protection/injury (HERYCA-P) protocol to study food-derive extracts. The method measures intracellular reactive oxygen species (ROS) generation, lipoperoxidation, and haemolysis induced by 2,2'-azobis(2-amidinopropane) dihydrochloride. Quercetin decreased ROS generation by 50.4% and haemolysis by 2.2%, while ascorbic acid inhibited lipid peroxidation by 40.1%. Total phenolic contents of teas were correlated with decreased ROS generation (r = -0.924), lipoperoxidation (r = -0.951), and haemolysis (r = -0.869). The erythrocyte ROS generation and lipoperoxidation were also associated with CUPRAC (r = -0.925; r = -0.951) and hydroxyl radical scavenging activity (r = -0.936; r = -0.949). The precision rates of antioxidant standards and tea samples were below 15%. HERYCA-P is feasible as a complementary antioxidant assay for food matrices.

H2S is involved in drought-mediated stomatal closure through PLDα1 in Arabidopsis

MAIN CONCLUSION

PLDα1 promoted H2S production by positively regulating the expression of LCD. Stomatal closure promoted by PLDα1 required the accumulation of H2S under drought stress. Phospholipase Dα1 (PLDα1) acting as one of the signal enzymes can respond to drought stress. It is well known that hydrogen sulfide (H2S) plays an important role in plant responding to biotic or abiotic stress. In this study, the functions and relationship between PLDα1 and H2S in drought stress resistance in Arabidopsis were explored. Our results indicated that drought stress promotes PLDα1 and H2S production by inducing the expression of PLDα1 and LCD genes. PLDα1 and LCD enhanced plant tolerance to drought by regulating membrane lipid peroxidation, proline accumulation, H2O2 content and stomatal closure. Under drought stress, the H2O2 content of PLDα1-deficient mutant (pldα1), L-cysteine desulfhydrase (LCD)-deficient mutant (lcd) was higher than that of ecotype (WT), the stomatal aperture of pldα1 and lcd was larger than that of WT. The transcriptional and translational levels of LCD were lower in pldα1 than that in WT. Exogenous application of the H2S donor NaHS or GYY reduced the stomatal aperture of WT, pldα1, PLDα1-CO, and PLDα1-OE lines, while exogenous application of the H2S scavenger hypotaurine (HT) increased the stomatal aperture. qRT-PCR analysis of stomatal movement-related genes showed that the expression of CAX1, ABCG5, SCAB1, and SLAC1 genes in pldα1 and lcd were down-regulated, while ACA1 and OST1 gene expression was significantly up-regulated. Thus, PLDα1 and LCD are required for stomatal closure to improve drought stress tolerance.

Alcohol-induced hormonal and metabolic alterations in plasma and erythrocytes-a gender-based study

PURPOSE

This study aimed to understand the gender-specific alcohol-induced biochemical changes and TBARS association with the endocrine system.

METHODS

Human male and female subjects ranging from 35 ± 10 years old with an 8-10-year drinking history were included in the study.

RESULTS

The results demonstrated that testosterone levels were lower in male alcoholics and higher in female alcoholics, as well as higher estrogen and cortisol levels in both genders. In addition, we found lower T3, T4, and thyroid-stimulating hormone (TSH) levels in alcoholics of both sexes. Furthermore, plasma TBARS, protein carbonyls, nitrite, and nitrate levels increased significantly with concomitant decrease in reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities in both male and female alcoholics. Furthermore, erythrocyte lysate nitrite and nitrate levels membrane total cholesterol, phospholipid and cholesterol/phospholipid (C/P) ratio with lower total membrane proteins in both genders of alcoholics. SDS-PAGE analysis of erythrocyte membrane proteins revealed increased density of band 3, protein 4.1, 4.2, 4.9 and glycophorins, whereas decreases in spectrin (α and β) were observed in both genders of alcoholics. Besides, alcoholics of both sexes had a lower ability to resist osmotic hemolysis. Plasma TBARS was negatively correlated with testosterone, TSH, T3 and T4 in male alcoholics, moreover, estradiol and cortisol were positively correlated in males and females respectively.

CONCLUSION

Female alcoholics may be more susceptible to osmotic hemolysis due to increased erythrocyte membrane lipid peroxidation with decreased antioxidant status, which results in an altered membrane C/P ratio and membrane protein composition.

Changes in the blood redox status of horses subjected to combat training

Combat training of police horses, involving physical activity in the presence of environmental stressors, poses a risk of oxidative stress. This study compared the oxidative imbalance after combat training in horses in the regular police service and in horses that had just been schooled. Blood collection was performed immediately after training and after 16 h rest. The activity of superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total antioxidant status (TAS) were determined as the markers of enzymatic antioxidant defence. At the same time, lipid peroxidation (TBARS) and protein carbonylation (Carb) were assessed as oxidation biomarkers. Additionally, oxidative imbalance indexes such as SOD/CAT, SOD/GPx, TBARS/TAS and TBARS/GPx were calculated. Animals during schooling had significantly lower SOD activity in erythrocytes than those experienced. CAT activity in erythrocytes was insignificantly higher immediately after training than during recovery. The SOD/GPx ratio was higher in experienced animals, which may reflect the intra-erythrocyte imbalance between enzymes producing and degrading hydrogen peroxide towards the first one. The concentration of carbonyl groups was significantly higher after the combat training compared to the recovery period in all horses. In inexperienced animals slight increase in TBARS/TAS and TBARS/GPx indexes were observed during the recovery time after exercises, contrary to experienced horses, in which these markers decreased slightly. These results suggest that the oxidative imbalance in inexperienced horses, although less pronounced just after combat training, was more prolonged as compared to horses in regular service.

LPCAT1-mediated membrane phospholipid remodelling promotes ferroptosis evasion and tumour growth

The mechanisms underlying the dynamic remodelling of cellular membrane phospholipids to prevent phospholipid peroxidation-induced membrane damage and evade ferroptosis, a non-apoptotic form of cell death driven by iron-dependent lipid peroxidation, remain poorly understood. Here we show that lysophosphatidylcholine acyltransferase 1 (LPCAT1) plays a critical role in ferroptosis resistance by increasing membrane phospholipid saturation via the Lands cycle, thereby reducing membrane levels of polyunsaturated fatty acids, protecting cells from phospholipid peroxidation-induced membrane damage and inhibiting ferroptosis. Furthermore, the enhanced in vivo tumour-forming capability of tumour cells is closely associated with the upregulation of LPCAT1 and emergence of a ferroptosis-resistant state. Combining LPCAT1 inhibition with a ferroptosis inducer synergistically triggers ferroptosis and suppresses tumour growth. Therefore, our results unveil a plausible role for LPCAT1 in evading ferroptosis and suggest it as a promising target for clinical intervention in human cancer.

Sensitivity of different organs and tissues as biomarkers of oxidative stress in juvenile tambaqui (Colossoma macropomum) submitted to fasting

The present study was conducted to evaluate the effects of fasting on responses of oxidative biomarkers and antioxidant defenses using different organs and tissues of Colossoma macropomum. The fish were divided into two groups: fed (control) and fasting (7 days). After 7 days, the fish were sampled for assessment of oxidative stress biomarkers (MDA-lipid peroxidation and PCO-protein carbonyl) and antioxidant defenses (SOD-superoxide dismutase; CAT-catalase; GPX-glutathione peroxidase; and GST-glutathione-S -transferase) in the liver, intestine, gills, muscle, brain, and plasma. The results showed an increase in MDA, PCO, SOD, and GPX concentrations in the liver and intestine of fasting fish. In contrast, in the branchial tissue, there was a reduction in the activity of SOD and CAT enzymes in fasting fish. There was also a reduction in CAT activity in the muscle of fasting fish, while in the brain, there were no changes in oxidative stress biomarkers. Plasma showed a relatively low antioxidant response. In conclusion, our results confirm that a 7-day fasting period induced tissue-specific antioxidant responses, but the increase in antioxidant responses was only for the SOD and GPX enzymes of the liver and intestine. Additionally, the liver and intestine were the most responsive tissues, whereas the plasma was the least sensitive to oxidative stress.

circFAM193B interaction with PRMT6 regulates AML leukemia stem cells chemoresistance through altering the oxidative metabolism and lipid peroxidation

Most forms of chemotherapy for acute myeloid leukemia (AML) are often ineffective in eliminating leukemic stem cells (LSCs), as their underlying mechanisms remain unclear. Here, we have identified circFAM193B, which regulates the redox biology of LSCs and is associated with unfavorable outcomes in AML patients. In vitro and in vivo assays suggested that circFAM193B significantly inhibits LSCs chemotherapy resistance and AML progression. Knockdown circFAM193B enhances mitochondrial OXPHOS function and inhibits the accumulation of reactive oxygen species and lipid peroxidation mediated by chemotherapy, which protects AML cells from oxidative stress-induced cell death. Mechanistically, circFAM193B physically interacts with arginine methyltransferase PRMT6 catalytic domain and enhances the transcription efficiency of key lipid peroxidation factor ALOX15 by decreasing H3R2me2a modification. In summary, we have identified circFAM193B was downregulated in LSCs to promote the survival of LSC by modulating energy metabolism and the redox balance in the postchemotherapy persistence of LSC. Our studies provide a conceptual advance and biological insights regarding the drug resistance of LSCs via circRNA mediated PRMT6-deposited methylarginine signaling.

The role of warming in modulating neodymium effects on adults and sperm of Mytilus galloprovincialis

The use of rare earth elements (REEs) has been increasing and one of the most used is neodymium (Nd). Being an emergent contaminant, its negative impacts are poorly understood. Aquatic organisms are also threatened by climate change-related factors, as is the case of warming, which can change the effects of REEs. Thus, the impacts of Nd, warming, and the combination of both stressors were studied in adult mussels and sperm of the species Mytilus galloprovincialis, after an exposure period of 28 days (adults) and 30 min (sperm). The effects were evaluated through the analysis of biochemical and histopathological alterations in adults and biochemical and physiological responses given by sperm. The results showed that mussels only activated their biotransformation capacity when exposed to the stressors acting alone, which was insufficient to avoid lipid peroxidation. Furthermore, warming (alone and combined with Nd) also produces damage to proteins. The digestive gland was the most sensitive organ to Nd, presenting several histopathological alterations. In the case of sperm, all stressors induced lipid peroxidation, a higher oxygen demand, and a decrease in velocity, even if the sperm viability was maintained. It seems that warming influenced the effects of Nd to some extent. The present findings contribute significantly to the field of REEs environmental toxicology by offering valuable insights into the impacts of Nd on various biological levels of mussels. Additionally, within the context of climate change, this study sheds light on how temperature influences the effects of Nd. The obtained results indicate that both stressors can potentially compromise the overall health of mussel populations, thereby affecting other species reliant on them for food and habitat. Moreover, this study highlights impaired sperm health, which could adversely affect their reproductive capacity and ultimately lead to population decline.

Icariin, astragaloside a and puerarin mixture attenuates cognitive impairment in APP/PS1 mice via inhibition of ferroptosis-lipid peroxidation

Alzheimer's disease (AD) is a neurodegenerative disease that seriously threatens the quality of life of the elderly. Its pathogenesis has not yet been fully elucidated. Ferroptosis, a cell death caused by excessive accumulation of iron-dependent lipid peroxides, has been implicated in the pathogenesis of AD. Uncontrolled lipid peroxidation is the core process of ferroptosis, and inhibiting lipid peroxidation of ferroptosis may be an important therapeutic target for AD. Based on previous studies, we mixed standards of icariin, astragaloside IV, and puerarin, named the standard mixture YHG, and investigated the effect of YHG on ferroptosis -lipid peroxidation in APP/PS1 mice. DFX, a ferroptosis inhibitor, was used as a control drug. In this study, APP/PS1 mice were used as an AD animal model, and behavioral experiments, iron level detection, Transmission electron microscopy (TEM) observation, lipid peroxidation level detection, antioxidant capacity detection, immunofluorescence, Western blot and real-time qPCR were performed. It was found that YHG could reduce body weight, significantly improve abnormal behaviors and the ultrastructure of hippocampal neurons in APP/PS1 mice. The results of biochemical tests showed that YHG reduced the contents of iron, malondialdehyde (MDA) and lipid peroxide (LPO) in brain tissue and serum, and increased the levels of superoxide dismutase (SOD) and reduced glutathione (GSH). Immunofluorescence, WesternBlot and real-time qPCR results showed that YHG could promote the expression of solute carrier family 7 member 11 (SLC7A11), solute carrier family 3 member 2 (SLC3A2) and glutathione peroxidase 4(GPX4). Inhibited the expression of long-chain acyllipid coenzyme a synthetase 4(ACSL4) and lysophosphatidyltransferase 3 (LPCAT3). This study suggests that the mechanism by which YHG improves cognitive dysfunction in APP/PS1 mice may be related to the inhibition of ferroptosis-lipid peroxidation.

New insights on neurodegeneration triggered by iron accumulation: Intersections with neutral lipid metabolism, ferroptosis, and motor impairment

Brain iron accumulation constitutes a pathognomonic indicator in several neurodegenerative disorders. Metal accumulation associated with dopaminergic neuronal death has been documented in Parkinson's disease. Through the use of in vivo and in vitro models, we demonstrated that lipid dysregulation manifests as a neuronal and glial response during iron overload. In this study, we show that cholesterol content and triacylglycerol (TAG) hydrolysis were strongly elevated in mice midbrain. Lipid cacostasis was concomitant with the loss of dopaminergic neurons, astrogliosis and elevated expression of α-synuclein. Exacerbated lipid peroxidation and markers of ferroptosis were evident in the midbrain from mice challenged with iron overload. An imbalance in the activity of lipolytic and acylation enzymes was identified, favoring neutral lipid hydrolysis, and consequently reducing TAG and cholesteryl ester levels. Notably, these observed alterations were accompanied by motor impairment in iron-treated mice. In addition, neuronal and glial cultures along with their secretomes were used to gain further insight into the mechanism underlying TAG hydrolysis and cholesterol accumulation as cellular responses to iron accumulation. We demonstrated that TAG hydrolysis in neurons is triggered by astrocyte secretomes. Moreover, we found that the ferroptosis inhibitor, ferrostatin-1, effectively prevents cholesterol accumulation both in neurons and astrocytes. Taken together, these results indicate that lipid disturbances occur in iron-overloaded mice as a consequence of iron-induced oxidative stress and depend on neuron-glia crosstalk. Our findings suggest that developing therapies aimed at restoring lipid homeostasis may lead to specific treatment for neurodegeneration associated with ferroptosis and brain iron accumulation.

Impact of changes in root biomass on the occurrence of internal browning in radish root

The purpose of this study was to investigate the effects of root biomass during the later stage of growth on fatty acid composition and lipid peroxidation, and to clarify the physiological mechanisms by which these differences affect internal browning (IB) development in radish roots. Therefore, we controlled the enlargement of roots by changing the thinning period and generated plots composed of roots with different biomass in the latter half of growth. The earlier the radish seedlings were thinned, the more vigorous the root growth from an earlier stage was achieved. Earlier thinning caused IB from the early stage of root maturation, and IB severity progressed with subsequent age progression; however, IB damage did not occur when root size during the later growth stage was kept small by later thinning. Higher levels of hydrogen peroxide, peroxidase activity, NADPH-dependent reactive oxygen species (ROS) burst-related genes, and carbonyl compounds were detected in earlier-thinned large-sized roots compared to later-thinned small-sized ones. Compared with the latter small-sized roots, the former large-sized roots had a lower ratio of linoleic acid (18:2) and a higher ratio of α-linolenic acid (α-18:3). Furthermore, in earlier-thinned large-sized roots, higher levels of phospholipase- and/or lipoxygenase-related genes were detected compared to later-thinned small-sized ones. These facts suggest the possibility that root biomass in the later stage of growth affects the desaturation of membrane fatty acids, ROS concentration, and activity of fatty acid degrading enzymes, and controls the occurrence of IB injury through membrane oxidative degradation.

A Bimetallic Polymerization Network for Effective Increase in Labile Iron Pool and Robust Activation of cGAS/STING Induces Ferroptosis-Based Tumor Immunotherapy

Due to the inherent low immunogenicity and immunosuppressive tumor microenvironment (TME) of malignant cancers, the clinical efficacy and application of tumor immunotherapy have been limited. Herein, a bimetallic drug-gene co-loading network (Cu/ZIF-8@U-104@siNFS1-HA) is developed that increased the intracellular labile iron pool (LIP) and enhanced the weakly acidic TME by co-suppressing the dual enzymatic activities of carbonic anhydrase IX (CA IX) and cysteine desulfurylase (NFS1), inducing a safe and efficient initial tumor immunogenic ferroptosis. During this process, Cu2+ is responsively released to deplete glutathione (GSH) and reduce the enzyme activity of glutathione peroxidase 4 (GPX4), achieving the co-inhibition of the three enzymes and further inducing lipid peroxidation (LPO). Additionally, the reactive oxygen species (ROS) storm in target cells promoted the generation of large numbers of double-stranded DNA breaks. The presence of Zn2+ substantially increased the expression of cGAS/STING, which cooperated with ferroptosis to strengthen the immunogenic cell death (ICD) response and remodel the immunosuppressive TME. In brief, Cu/ZIF-8@U-104@siNFS1-HA linked ferroptosis with immunotherapy through multiple pathways, including the increase in LIP, regulation of pH, depletion of GSH/GPX4, and activation of STING, effectively inhibiting cancer growth and metastasis.

Identification of a set of genes potentially responsible for resistance to ferroptosis in lung adenocarcinoma cancer stem cells

Scientific literature supports the evidence that cancer stem cells (CSCs) retain inside low reactive oxygen species (ROS) levels and are, therefore, less susceptible to cell death, including ferroptosis, a type of cell death dependent on iron-driven lipid peroxidation. A collection of lung adenocarcinoma (LUAD) primary cell lines derived from malignant pleural effusions (MPEs) of patients was used to obtain 3D spheroids enriched for stem-like properties. We observed that the ferroptosis inducer RSL3 triggered lipid peroxidation and cell death in LUAD cells when grown in 2D conditions; however, when grown in 3D conditions, all cell lines underwent a phenotypic switch, exhibiting substantial resistance to RSL3 and, therefore, protection against ferroptotic cell death. Interestingly, this phenomenon was reversed by disrupting 3D cells and growing them back in adherence, supporting the idea of CSCs plasticity, which holds that cancer cells have the dynamic ability to transition between a CSC state and a non-CSC state. Molecular analyses showed that ferroptosis resistance in 3D spheroids correlated with an increased expression of antioxidant genes and high levels of proteins involved in iron storage and export, indicating protection against oxidative stress and low availability of iron for the initiation of ferroptosis. Moreover, transcriptomic analyses highlighted a novel subset of genes commonly modulated in 3D spheroids and potentially capable of driving ferroptosis protection in LUAD-CSCs, thus allowing to better understand the mechanisms of CSC-mediated drug resistance in tumors.

Therapeutic exploitation of ferroptosis

Pathological breakdown of membrane lipids through excessive lipid peroxidation (LPO) was first described in the mid-20th century and is now recognized as a form of regulated cell death, dubbed ferroptosis. Accumulating evidence unveils how metabolic regulation restrains peroxidation of phospholipids within cellular membranes, thereby impeding ferroptosis execution. Unleashing these metabolic breaks is currently therapeutically explored to sensitize cancers to ferroptosis inducing anti-cancer therapies. Reversely, these natural ferroptotic defense mechanisms can fail resulting in pathological conditions or diseases such as ischemia-reperfusion injury, multi-organ dysfunction, stroke, infarction, or neurodegenerative diseases. This minireview outlines current ferroptosis-inducing anti-cancer strategies and highlights the detection as well as the therapeutic targeting of ferroptosis in preclinical experimental settings. Herein, we also briefly summarize observations related to LPO, iron and redox deregulation in patients that might hint towards ferroptosis as a contributing factor.

Fatty acid-binding protein 5 is a functional biomarker and indicator of ferroptosis in cerebral hypoxia

The progression of human degenerative and hypoxic/ischemic diseases is accompanied by widespread cell death. One death process linking iron-catalyzed reactive species with lipid peroxidation is ferroptosis, which shows hallmarks of both programmed and necrotic death in vitro. While evidence of ferroptosis in neurodegenerative disease is indicated by iron accumulation and involvement of lipids, a stable marker for ferroptosis has not been identified. Its prevalence is thus undetermined in human pathophysiology, impeding recognition of disease areas and clinical investigations with candidate drugs. Here, we identified ferroptosis marker antigens by analyzing surface protein dynamics and discovered a single protein, Fatty Acid-Binding Protein 5 (FABP5), which was stabilized at the cell surface and specifically elevated in ferroptotic cell death. Ectopic expression and lipidomics assays demonstrated that FABP5 drives redistribution of redox-sensitive lipids and ferroptosis sensitivity in a positive-feedback loop, indicating a role as a functional biomarker. Notably, immunodetection of FABP5 in mouse stroke penumbra and in hypoxic postmortem patients was distinctly associated with hypoxically damaged neurons. Retrospective cell death characterized here by the novel ferroptosis biomarker FABP5 thus provides first evidence for a long-hypothesized intrinsic ferroptosis in hypoxia and inaugurates a means for pathological detection of ferroptosis in tissue.

Lipid Peroxidation-Related Redox Signaling in Osteosarcoma

Oxidative stress and lipid peroxidation play important roles in numerous physiological and pathological processes, while the bioactive products of lipid peroxidation, lipid hydroperoxides and reactive aldehydes, act as important mediators of redox signaling in normal and malignant cells. Many types of cancer, including osteosarcoma, express altered redox signaling pathways. Such redox signaling pathways protect cancer cells from the cytotoxic effects of oxidative stress, thus supporting malignant transformation, and eventually from cytotoxic anticancer therapies associated with oxidative stress. In this review, we aim to explore the status of lipid peroxidation in osteosarcoma and highlight the involvement of lipid peroxidation products in redox signaling pathways, including the involvement of lipid peroxidation in osteosarcoma therapies.

Overview of the Lipid Peroxidation Measurements in Patients by the Enzyme-Linked Immunosorbent Assay Specific for the 4-Hydroxynonenal-Protein Adducts (4-HNE-ELISA)

Oxidative stress often affects the structure and metabolism of lipids, which in the case of polyunsaturated free fatty acids (PUFAs) leads to a self-catalysed chain reaction of lipid peroxidation (LPO). The LPO of PUFAs leads to the formation of various aldehydes, such as malondialdehyde, 4-hydroxynonenal (4-HNE), 4-hydroxyhexenal, and 4-oxo-2-nonenal. Among the reactive aldehydes, 4-HNE is the major bioactive product of LPO, which has a high affinity for binding to proteins. This review briefly discusses the available information on the applicability of assessment options for 4-HNE and its protein adducts determined by immunosorbent assay (the 4-HNE-ELISA) in patients with various diseases known to be associated with oxidative stress, LPO, and 4-HNE. Despite the differences in the protocols applied and the antibodies used, all studies confirmed the usefulness of the 4-HNE-ELISA for research purposes. Since different protocols and the antibodies used could give different values when applied to the same samples, the 4-HNE-ELISA should be combined with other complementary analytical methods to allow comparisons between the values obtained in patients and in healthy individuals. Despite large variations, the studies reviewed in this paper have mostly shown significantly increased levels of 4-HNE-protein adducts in the samples obtained from patients when compared to healthy individuals. As with any other biomarker studied in patients, it is preferred to perform not only a single-time analysis but measurements at multiple time points to monitor the dynamics of the occurrence of oxidative stress and the systemic response to the disease causing it. This is especially important for acute diseases, as individual levels of 4-HNE-protein adducts in blood can fluctuate more than threefold within a few days depending on the state of health, as was shown for the COVID-19 patients.

USP8-governed GPX4 homeostasis orchestrates ferroptosis and cancer immunotherapy

Ferroptosis is an iron-dependent type of regulated cell death resulting from extensive lipid peroxidation and plays a critical role in various physiological and pathological processes. However, the regulatory mechanisms for ferroptosis sensitivity remain incompletely understood. Here, we report that homozygous deletion of Usp8 (ubiquitin-specific protease 8) in intestinal epithelial cells (IECs) leads to architectural changes in the colonic epithelium and shortens mouse lifespan accompanied by increased IEC death and signs of lipid peroxidation. However, mice with heterozygous deletion of Usp8 in IECs display normal phenotype and become resistant to azoxymethane/dextran sodium sulfate-induced colorectal tumorigenesis. Mechanistically, USP8 interacts with and deubiquitinates glutathione peroxidase 4 (GPX4), leading to GPX4 stabilization. Thus, USP8 inhibition destabilizes GPX4 and sensitizes cancer cells to ferroptosis in vitro. Notably, USP8 inhibition in combination with ferroptosis inducers retards tumor growth and enhances CD8+ T cell infiltration, which potentiates tumor response to anti-PD-1 immunotherapy in vivo. These findings uncover that USP8 counteracts ferroptosis by stabilizing GPX4 and highlight targeting USP8 as a potential therapeutic strategy to boost ferroptosis for enhancing cancer immunotherapy.

The Role of Oxidative Stress in Alcoholic Fatty Liver Disease: A Systematic Review and Meta-Analysis of Preclinical Studies

Alcoholic Fatty Liver Disease (AFLD) is characterized by the accumulation of lipids in liver cells owing to the metabolism of ethanol. This process leads to a decrease in the NAD+/NADH ratio and the generation of reactive oxygen species. A systematic review and meta-analysis were conducted to investigate the role of oxidative stress in AFLD. A total of 201 eligible manuscripts were included, which revealed that animals with AFLD exhibited elevated expression of CYP2E1, decreased enzymatic activity of antioxidant enzymes, and reduced levels of the transcription factor Nrf2, which plays a pivotal role in the synthesis of antioxidant enzymes. Furthermore, animals with AFLD exhibited increased levels of lipid peroxidation markers and carbonylated proteins, collectively contributing to a weakened antioxidant defense and increased oxidative damage. The liver damage in AFLD was supported by significantly higher activity of alanine and aspartate aminotransferase enzymes. Moreover, animals with AFLD had increased levels of triacylglycerol in the serum and liver, likely due to reduced fatty acid metabolism caused by decreased PPAR-α expression, which is responsible for fatty acid oxidation, and increased expression of SREBP-1c, which is involved in fatty acid synthesis. With regard to inflammation, animals with AFLD exhibited elevated levels of pro-inflammatory cytokines, including TNF-a, IL-1β, and IL-6. The heightened oxidative stress, along with inflammation, led to an upregulation of cell death markers, such as caspase-3, and an increased Bax/Bcl-2 ratio. Overall, the findings of the review and meta-analysis indicate that ethanol metabolism reduces important markers of antioxidant defense while increasing inflammatory and apoptotic markers, thereby contributing to the development of AFLD.

Role of ferroptosis in fibrosis: From mechanism to potential therapy

ABSTRACT

Fibrosis, which is a manifestation of the physiological response to injury characterized by excessive accumulation of extracellular matrix components, is a ubiquitous outcome of the repair process. However, in cases of repetitive or severe injury, fibrosis may become dysregulated, leading to a pathological state and organ failure. In recent years, a novel form of regulated cell death, referred to as ferroptosis, has been identified as a possible contributor to fibrosis; it is characterized by iron-mediated lipid peroxidation. It has garnered attention due to the growing body of evidence linking ferroptosis and fibrogenesis, which is believed to be driven by underlying inflammation and immune responses. Despite the increasing interest in the relationship between ferroptosis and fibrosis, a comprehensive understanding of the precise role that ferroptosis plays in the formation of fibrotic tissue remains limited. This review seeks to synthesize previous research related to the topic. We categorized the different direct and indirect mechanisms by which ferroptosis may contribute to fibrosis into three categories: (1) iron overload toxicity; (2) ferroptosis-evoked necroinflammation, with a focus on ferroptosis and macrophage interplay; and (3) ferroptosis-associated pro-fibrotic factors and pathways. Furthermore, the review considers the potential implications of these findings and highlights the utilization of ferroptosis-targeted therapies as a promising strategy for mitigating the progression of fibrosis. In conclusion, novel anti-fibrotic treatments targeting ferroptosis could be an effective treatment for fibrosis.

Exogenous ascorbic acid as a potent regulator of antioxidants, osmo-protectants, and lipid peroxidation in pea under salt stress

Pea (Pisum sativum L.), a globally cultivated leguminous crop valued for its nutritional and economic significance, faces a critical challenge of soil salinity, which significantly hampers crop growth and production worldwide. A pot experiment was carried out in the Botanical Garden, The Islamia University of Bahawalpur to alleviate the negative impacts of sodium chloride (NaCl) on pea through foliar application of ascorbic acid (AsA). Two pea varieties Meteor (V1) and Sarsabz (V2) were tested against salinity, i.e. 0 mM NaCl (Control) and 100 mM NaCl. Three levels of ascorbic acid 0 (Control), 5 and 10 mM were applied through foliar spray. The experimental design was completely randomized (CRD) with three replicates. Salt stress resulted in the suppression of growth, photosynthetic activity, and yield attributes in pea plants. However, the application of AsA treatments effectively alleviated these inhibitory effects. Under stress conditions, the application of AsA treatment led to a substantial increase in chlorophyll a (41.1%), chl. b (56.1%), total chl. contents (44.6%) and carotenoids (58.4%). Under salt stress, there was an increase in Na+ accumulation, lipid peroxidation, and the generation of reactive oxygen species (ROS). However, the application of AsA increased the contents of proline (26.9%), endogenous AsA (23.1%), total soluble sugars (17.1%), total phenolics (29.7%), and enzymatic antioxidants i.e. SOD (22.3%), POD (34.1%) and CAT (39%) in both varieties under stress. Salinity reduced the yield attributes while foliarly applied AsA increased the pod length (38.7%), number of pods per plant (40%) and 100 seed weight (45.2%). To sum up, the application of AsA alleviated salt-induced damage in pea plants by enhancing photosynthetic pigments, both enzymatic and non-enzymatic activities, maintaining ion homeostasis, and reducing excessive ROS accumulation through the limitation of lipid peroxidation. Overall, V2 (Sarsabz) performed better as compared to the V1 (Meteor).

Mapping the Research of Ferroptosis in Parkinson's Disease from 2013 to 2023: A Scientometric Review

Methods

Related studies on PD and ferroptosis were searched in Web of Science Core Collection (WOSCC) from inception to 2023. VOSviewer, CiteSpace, RStudio, and Scimago Graphica were employed as bibliometric analysis tools to generate network maps about the collaborations between authors, countries, and institutions and to visualize the co-occurrence and trends of co-cited references and keywords.

Results

A total of 160 original articles and reviews related to PD and ferroptosis were retrieved, produced by from 958 authors from 162 institutions. Devos David was the most prolific author, with 9 articles. China and the University of Melbourne had leading positions in publication volume with 84 and 12 publications, respectively. Current hot topics focus on excavating potential new targets for treating PD based on ferroptosis by gaining insight into specific molecular mechanisms, including iron metabolism disorders, lipid peroxidation, and imbalanced antioxidant regulation. Clinical studies aimed at treating PD by targeting ferroptosis remain in their preliminary stages.

Conclusion

A continued increase was shown in the literature within the related field over the past decade. The current study suggested active collaborations among authors, countries, and institutions. Research into the pathogenesis and treatment of PD based on ferroptosis has remained a prominent topic in the field in recent years, indicating that ferroptosis-targeted therapy is a potential approach to halting the progression of PD.

In-Depth Profiling of 4-Hydroxy-2-nonenal Modification via Reversible Thiazolidine Chemistry

Protein modification by lipid-derived electrophiles (LDEs) is associated with various signaling pathways. Among these LDEs, 4-hydroxy-2-nonenal (HNE) is the most toxic, and protein modified with HNE has been linked to various diseases, including Alzheimer's and Parkinson's. However, due to their low abundance, in-depth profiling of HNE modifications still presents challenges. This study introduces a novel strategy utilizing reversible thiazolidine chemistry to selectively capture HNE-modified proteins and a palladium-mediated cleavage reaction to release them. Thousands of HNE-modified sites in different cell lines were identified. Combined with ABPP, we discovered a set of HNE-sensitive sites that offer a new tool for studying LDE modifications in proteomes.

SBFI26 induces triple-negative breast cancer cells ferroptosis via lipid peroxidation

SBFI26, an inhibitor of FABP5, has been shown to suppress the proliferation and metastasis of tumour cells. However, the underlying mechanism by which SBFI26 induces ferroptosis in breast cancer cells remains largely unknown. Three breast cancer cell lines were treated with SBFI26 and CCK-8 assessed cytotoxicity. Transcriptome was performed on the Illumina platform and verified by qPCR. Western blot evaluated protein levels. Malondialdehyde (MDA), total superoxide dismutase (T-SOD), Fe, glutathione (GSH) and oxidized glutathione (GSSG) were measured. SBFI26 induced cell death time- and dose-dependent, with a more significant inhibitory effect on MDA-MB-231 cells. Fer-1, GSH and Vitamin C attenuated the effects but not erastin. RNA-Seq analysis revealed that SBFI26 treatment significantly enriched differentially expressed genes related to ferroptosis. Furthermore, SBFI26 increased intracellular MDA, iron ion, and GSSG levels while decreasing T-SOD, total glutathione (T-GSH), and GSH levels.SBFI26 dose-dependently up-regulates the expression of HMOX1 and ALOX12 at both gene and protein levels, promoting ferroptosis. Similarly, it significantly increases the expression of SAT1, ALOX5, ALOX15, ALOXE3 and CHAC1 that, promoting ferroptosis while downregulating the NFE2L2 gene and protein that inhibit ferroptosis. SBFI26 leads to cellular accumulation of fatty acids, which triggers excess ferrous ions and subsequent lipid peroxidation for inducing ferroptosis.

Ferroptosis in age-related vascular diseases: Molecular mechanisms and innovative therapeutic strategies

Aging, an inevitable aspect of human existence, serves as one of the predominant risk factors for vascular diseases. Delving into the mystery of vascular disease's pathophysiology, the profound involvement of programmed cell death (PCD) has been extensively demonstrated. PCD is a fundamental biological process that plays a crucial role in both normal physiology and pathology, including a recently discovered form, ferroptosis. Ferroptosis is characterized by its reliance on iron and lipid peroxidation, and its significant involvement in vascular disease pathophysiology has been increasingly acknowledged. This phenomenon not only offers a promising therapeutic target but also deepens our understanding of the complex relationship between ferroptosis and age-related vascular diseases. Consequently, this article aims to thoroughly review the mechanisms that enable the effective control and inhibition of ferroptosis. It focuses on genetic and pharmacological interventions, with the goal of developing innovative therapeutic strategies to combat age-related vascular diseases.

Oxidative stress in the bivalve Diplodon chilensis under direct and dietary glyphosate-based formulation exposure

The aim of this study was to evaluate and compare the effects on biochemical parameters and organosomatic indices in the freshwater bivalve Diplodon chilensis exposed to a glyphosate-based formulation under direct and dietary exposures (4 mg a.p./L). After 1, 7, and 14 days of exposure, reduced glutathione (GSH) and thiobarbituric acid reactive substances (TBARS) levels and the activities of glutathione-S- transferase (GST), superoxide dismutase (SOD), and catalase (CAT) were evaluated in the gills and digestive gland. The hepatosomatic (HSI) and branchiosomatic (BSI) indices were also analyzed. Direct and dietary glyphosate-based formulation exposure altered the redox homeostasis in the gills and digestive gland throughout the experimental time, inducing the detoxification response (GST), the antioxidant defenses (SOD, CAT, GSH), and causing lipid peroxidation. After 14 days of exposure, the HSI and BSI increased significantly (43% and 157%, respectively) only in the bivalves under direct exposure. Greater changes in the biochemical parameters were induced by the dietary exposure than by the direct exposure. Furthermore, the gills presented an earlier response compared to the digestive gland. These results suggested that direct and dietary exposure to a glyphosate-based formulation induced oxidative stress in the gills and digestive glands of D. chilensis. Thus, the presence of glyphosate-based formulations in aquatic ecosystems could represent a risk for filter-feeding organisms like bivalves.

Laser-Ignited Lipid Peroxidation Nanoamplifiers for Strengthening Tumor Photodynamic Therapy Through Aggravating Ferroptotic Propagation and Sustainable High Immunogenicity

Photodynamic therapy (PDT) is extensively investigated for tumor therapy in the clinic. However, the efficacy of PDT is severely limited by the tissue penetrability of light, short effective half-life and radius of reactive oxygen species (ROS), and the weak immunostimulatory effect. In this study, a glutathione (GSH)-activatable nano-photosensitizer is developed to load with arachidonic acid (AA) and camouflage by erythrocyte membrane, which serves as a laser-ignited lipid peroxidation nanoamplifier (MAR). The photosensitive effect of MAR is recovered accompanied by the degradation in the tumor microenvironment and triggers the peroxidation of AA upon laser excitation. Interestingly, it aggravates the propagation of ferroptosis among cancer cells by driving the continuous lipid peroxidation chain reactions with the participation of the degradation products, ferrous ions (Fe2+), and AA. Consequently, even the deep-seated tumor cells without illumination also undergo ferroptosis owing to the propagation of ferroptotic signal. Moreover, the residual tumor cells undergoing ferroptosis still maintain high immunogenicity after PDT, thus continuously triggering sufficient tumor-associated antigens (TAAs) release to remarkably promote the anti-tumor immune response. Therefore, this study will provide a novel "all-in-one" nano-photosensitizer that not only amplifies the damaging effect and expands the effective range of PDT but also improves the immunostimulatory effect after PDT.

Interactive impacts of CO2-induced seawater acidification and cadmium exposure on antioxidant defenses of juvenile tongue sole Cynoglossus semilaevis

Antioxidant responses of juvenile sole exposed to seawater acidification (SA) and Cd were investigated. SA increased lipid peroxidation (LPO) in the fish, independent of Cd concentrations. Cd at medium and high levels inflated LPO under no or moderate SA conditions. This effect was absent under high SA levels, due to SA effect exceeding and obscuring Cd effect. SA and Cd collaborated to provoke LPO, with SOD and CAT being stimulated to defend against oxidative stress, while those related to GSH redox cycle were inhibited under SA exposure. Responses of GSH-related antioxidants to Cd impact varied contingent on their interactions with SA. This defensive strategy was insufficient to protect fish from increased LPO. Antioxidants responded more sensitively to SA than Cd exposure. GSH, GR, SOD and CAT are sensitive biomarkers for SA conditions. The findings offer insights into assessing fish's antioxidant defense strategy under Cd and SA circumstances in natural habitats.

Understanding baseline levels of physiological stress tolerance from excessive exercise in a holobenthic octopus species, Octopus pallidus

Cephalopods receive a great deal of attention due to their socioeconomically important fisheries and aquaculture industries as well their unique biological features. However, basic information about their physiological responses under stress conditions is lacking. This study investigated the impact of a simple stressor, exercise to exhaustion, on the activity levels of antioxidant enzymes and the concentrations of molecules involved in oxidative stress response in the pale octopus (Octopus pallidus). Eight biochemical assays were measured in the humoral (plasma) and cellular (hemocyte) components of O. pallidus haemolymph, the invertebrate analogue to vertebrate blood. Overall, exercise resulted in an increase in activity of plasma catalase (CAT) and glutathione-S-transferase (GST) and the decrease in activity of plasms glutathione reductase (GR). In the hemocytes, the exercise elicited a different response, with a reduction in the activity of superoxide dismutase (SOD), GR, and glutathione peroxidase (GPX) and a reduction in nitric oxide (NO) concentration. Malondialdehyde (MDA) activity was similar in the plasma and haemocytes in control and exercised treatments, indicating that exercise did not induce lipid peroxidation. These results provide an important baseline for understanding oxidative stress in octopus, with exercise to exhaustion serving as a simple stressor which will ultimately inform our ability to detect and understand physiological responses to more complex stressors.

Assessing physiological responses and oxidative stress effects in Rhamdia voulezi exposed to high temperatures

Exposure to high temperatures induces changes in fish respiration, resulting in an increased production of reactive oxygen species. This, in turn, affects the enzymatic and non-enzymatic components of antioxidant defenses, which are essential for mitigating cellular stress. Rhamdia voulezi, an economically important fish species endemic to Brazil's Iguaçu River, served as the subject of our study. Our goal was to assess enzymatic antioxidant biomarkers (superoxide dismutase, catalase, glutathione peroxidase, glutathione S-transferase, glutathione reductase, glucose-6-phosphate dehydrogenase), non-protein thiol levels (reduced glutathione), and markers of oxidative damage (lipoperoxidation and carbonylation) in the liver, gills, and kidneys of R. voulezi after acute exposure to high temperatures (31°C) for 2, 6, 12, 24, and 96 h. Control groups were maintained at 21°C. Our findings revealed that the liver exhibited increased superoxide dismutase levels up to 12 h and elevated glutathione S-transferase levels at 12 and 96 h at 31°C. In the gills, superoxide dismutase levels increased up to 24 h, along with increased lipoperoxidation at 2, 6, 12, and 96 h of exposure to high temperatures. The kidneys responded to heat stress at 12 h, with an increase in superoxide dismutase and catalase activity, and lipid peroxidation was observed at 2 and 6 h at 31°C. The three tissues evaluated responded differently to heat stress, with the liver demonstrating greater physiological adjustment to high temperatures. The intricate interplay of various antioxidant defense biomarkers and oxidative damage suggests the presence of oxidative stress in R. voulezi when exposed to high temperatures.

Nephro-protective effects of alpha-lipoic acid in type I diabetes

Type 1 diabetes (T1D) is an insulin-dependent autoimmune condition. Short chain fatty acids (SCFAs) are volatile fatty acids with 1-6 carbon atoms that influence glucose storage in the body and can reduce appetite, potentially decreasing T1D risk. Alpha-lipoic acid (α-LA), a type of SCFA, has previously been used to treat diabetic neuropathy and inflammation due to its antioxidant properties. This study aims to assess α-LA's protective effects against T1D and associated kidney damage in rats induced with streptozotocin. Diabetic rats were treated with α-LA orally for 15 days, resulting in improved blood glucose (56% decrease) and kidney function markers like blood urea nitrogen, creatinine and uric acid. α-LA also showed significant antioxidant effects by decreasing LPO as well as improving activities of antioxidant enzymes like superoxide dismutase, catalase and glutathione-S transferase and alleviated kidney damage caused by diabetes. Docking experiments suggest that α-LA may regulate diabetes-related changes at the epigenetic level through interactions with the SIRT1 protein, indicating its potential as a target for future antidiabetic drug development.

The influence of lifestyle and biological factors on semen variability

PURPOSE

Semen parameters are subjected to within-individual variability over time. The driving factors for this variability are likely multi-factorial, with healthier lifestyle associated with better semen quality. The extent in which variations in individual's lifestyle contributes to within-individual semen variability is unknown.

METHODS

A total of 116 repeat semen samples from 29 men aged 19-37 over 6 months were collected. Basic semen analysis as per 5th WHO manual and extended semen parameters (sperm DNA fragmentation, redox potential and lipid peroxidation, sperm binding to hyaluronan and hyperactive motility) were assessed. An additional 39 lifestyle/biological factors (weight, blood pressure, etc.) were collected at each sample including validated health questionnaires SF36 Health Status, Australian Recommend Food Score, and International Physical Activity Questionnaire.

RESULTS

Only 10 out of the 39 lifestyle factors varied within men across samples including age (P = 0.0024), systolic blood pressure (P = 0.0080), social functioning (P = 0.0340), energy (P = 0.0069), non-alcoholic caffeinated beverages (P = 0.0010), and nutrition (P < 0.0001). The only semen parameter that varied between collections was sperm morphology (coefficient of variation 23.8 (6.1-72.0), P < 0.05). We only observed weak (r < 0.3) to moderate (r > 0.3- < 0.6) correlations between lifestyle factors, including body mass index, waist circumference, nutrition, exercise, blood pressure and semen parameters including sperm count, progressive motility, and sperm DNA fragmentation (P < 0.05).

CONCLUSION

In healthy men from the general population, semen quality and associated lifestyle factors do not significantly vary over 6 months, indicating that one semen sample is likely sufficient for determining male fertility in this population.

A New Perspective in the Treatment of Ischemic Stroke: Ferroptosis

Ischemic stroke is a common neurological disease. Currently, there are no Food and Drug Administration-approved drugs that can maximize the improvement in ischemic stroke-induced nerve damage. Hence, treating ischemic stroke remains a clinical challenge. Ferroptosis has been increasingly studied in recent years, and it is closely related to the pathophysiological process of ischemic stroke. Iron overload, reactive oxygen species accumulation, lipid peroxidation, and glutamate accumulation associated with ferroptosis are all present in ischemic stroke. This article focuses on describing the relationship between ferroptosis and ischemic stroke and summarizes the relevant substances that ameliorate ischemic stroke-induced neurological damage by inhibiting ferroptosis. Finally, the problems in the treatment of ischemic stroke targeting ferroptosis are discussed, hoping to provide a new direction for its treatment.

Copper Exposure Induced Chicken Hepatotoxicity: Involvement of Ferroptosis Mediated by Lipid Peroxidation, Ferritinophagy, and Inhibition of FSP1-CoQ10 and Nrf2/SLC7A11/GPX4 Axis

Copper (Cu) is one of the most significant trace elements in the body, but it is also a widespread environmental toxicant health. Ferroptosis is a newly identified programmed cell death, which involves various heavy metal-induced organ toxicity. Nevertheless, the role of ferroptosis in Cu-induced hepatotoxicity remains poorly understood. In this study, we found that 330 mg/kg Cu could disrupt the liver structure and cause characteristic morphological changes in mitochondria associated with ferroptosis. Additionally, Cu treatment increased MDA (malondialdehyde) and LPO (lipid peroxide) production while reducing GSH (reduced glutathione) content and GCL (glutamate cysteine ligase) activity. However, it is noticeable that there were no appreciable differences in liver iron content and key indicators of iron metabolism. Meanwhile, our further investigation found that 330 mg/kg Cu-exposure changed multiple ferroptosis-related indicators in chicken livers, including inhibition of the expression of SLC7A11, GPX4, FSP1, and COQ10B, whereas enhances the levels of ACLS4, LPCAT3, and LOXHD1. Furthermore, the changes in the expression of NCOA4, TXNIP, and Nrf2/Keap1 signaling pathway-related genes and proteins also further confirmed 330 mg/kg Cu exposure-induced ferroptosis. In conclusion, our results indicated that ferroptosis may play essential roles in Cu overload-induced liver damage, which offered new insights into the pathogenesis of Cu-induced hepatotoxicity.